(676b) Near Infrared, One-Photon Triggered Liposome Cage for Calcium, ATP or Both

Authors: 
Zasadzinski, J. A., University of Minnesota
Shin, J., University of Minnesota
Ogunyankin, M. O., Bristol-Myers Squibb
Veeren, A., University of Minnesota
We describe a one-photon, near infrared triggered carrier for calcium, adenosine triphosphate, and potentially any small water-soluble bioactive molecule using unilamellar liposomes tethered to plasmon-resonant hollow gold nanoshells (HGN). Picosecond or shorter pulses of NIR light, available in conventional two-photon microscopes, at a fluence dependent on the plasmon resonance, size, and liposome composition, are adsorbed by the HGN, which rapidly heat, then dissipate that heat by forming vapor nanobubbles that ruptures the liposome carrier, releasing the calcium, ATP or other liposome contents within milliseconds. The spatial resolution is set by the size of the liposome carrier, as is the amount of encapsulated molecule released. This carrier system is universal and can release any small molecule at the same rate and in the same fashion, unlike current chelating cages for ions or photolabile protecting groups for biomolecules that require different chemical synthesis to achieve. By using liposomes of different composition and HGN with different nanobubble threshold fluences, two different caged molecules can be released simultaneously, or one before the other, or in a desired ratio. The vesicle and the HGN are biocompatible and provide complete and stable separation of the bioactive compound from its surroundings until triggered by NIR light. We will present our initial findings of release in various cell lines.